Review: Polivoks Pro Polivoks

A unique duophonic, analog synth returns from the past
Publish date:

It seems as if classic synth designs are being reissued (with and without proper licensing) at an increasing rate these days. When it’s done well, the sound and features of a popular synth are made available to a wider audience and for a lot less (especially the software versions) than the original costs on the collector’s market. And if better components and build methods are used, the cloned instrument will be less trouble to maintain than the original, which typically requires extra money for restoration and upkeep.

The Polivoks brings the aggressive sound of a classic Soviet keyboard synth to the desktop.

The Polivoks brings the aggressive sound of a classic Soviet keyboard synth to the desktop.

Remarkably, one of the most popular vintage synths from Soviet times, the Polivoks, has not received the attention that Western instruments of the same era by ARP, Moog, or Korg have gotten. That is, until now.

Designed and built in Russia by Alexey Taber and Alex Pleninger (with “recommendations and analysis” provided by Vladimir Kuzmin, the instrument’s original inventor), the new Polivoks delivers the overall sound quality and important features of the original, but in a desktop format suitable for contemporary music making.


Manufactured from the early ’80s through the end of the Soviet era, the Polivoks keyboard was an duophonic, analog instrument with a paraphonic implementation, where the two oscillators utilize the same filter and VCA. As a performance instrument, it was a little odd compared to synths outside the Easter Bloc, with its 48 keys (F to E!) and lack of pitch-bend and mod wheels. But most importantly, it had a unique tonal character.

Once electronic instruments began making their way out of post-Soviet Russia, the Polivoks gained popularity for its ability to create extreme tones. This had as much to do with the implementation of the modulation and envelope generators as it did with its atypical filter design.

When Taber and Pleninger decided to re-create the Polivoks, they took the bold step of altering the design. With MIDI and CV/gate connectivity now onboard, they could remove the keyboard, significantly reducing the overall size of the new synth. And while sticking to the original schematics as closely as possible, they reduced the size and weight of the instrument wherever they could (for example, using an external power supply) bringing the weight down to 6.6 lbs. from the original’s 44 lbs. The result is a more portable, desktop version of the Polivoks that not only stays true to the vintage sound but is capable of extending its timbral range.


This new Polivoks feels well-built and substantial and is housed in a metal chassis with MDF ends that, together, measure 17” x 7” (making it potentially rack-mountable if rack-ears become available). The synth is made in Moscow in a limited edition of 100 units and can be ordered from the company’s website.

Although the feature layout is straightforward, the front panel will take time to figure out if you don’t read Russian. Fortunately, an English-language overlay and PDF manual are available online, and a translation of most terms is printed on the bottom panel of the synth.

In Russian, the Polivoks VCOs are referred to as Generator 1 and 2, the LFO as Modulator, and so on. For this review, I’ll use the standard English terms, as shown in the overlay (Figure 1). For example, the LFO (Rate and Waveform) in the upper left with master controls below, the VCOs and mixer in the middle, followed by the resonant VCF and VCA on the right.

Fig. 1. If you’re unfamiliar with the Russian language, don’t worry: An English-language overlay is available online. As you can see, the layout of the Polivoks is easy to understand.

Fig. 1. If you’re unfamiliar with the Russian language, don’t worry: An English-language overlay is available online. As you can see, the layout of the Polivoks is easy to understand.


The first three knobs on both VCOs are the same: There is an octave selector with settings based on organ-stop pipe lengths (32', 16', 8', 4', 2'), a waveform selector (triangle, saw, and three pulse shapes—wide to narrow), and LFO Depth. The remaining control on VCO 1, Oscillator 2 FM, determines the amount of frequency modulation from VCO 2. The Polivoks’ ability to combine different frequency modulation levels from the LFO and VCO 2 is very exciting. Interestingly, you get the tangiest FM sounds when VCO 1 is set to a pulse wave.

The Master Tune knob, on the far left, affects both VCOs, but is the only tuning control available for VCO 1. The fourth knob for VCO 2 is a secondary tuning control, so you can dial in a fat unison sound or ratchet up the modulation over VCO 1.

The Polivoks VCOs have a remarkably big sound, even before you add modulation or filtering. But whether controlled by MIDI or CV, you will hear a noticeable difference between the two oscillators in terms of tracking. VCO 1 is the more accurate of the two across the 7-octave range I explored. So, if you’re looking for a truly vintage synth experience, here it is. Love it or hate it, this subtle inconsistency is part of what gives the Polivoks its musical character.

Speaking of which, an important addition to the Polivoks design is the RingMod output in the mixer, which combines rectangle waves from both VCOs and boosts the signal into soft limiting when the level is maxed. A similar boost has been added to the Noise output, although the noise ducks out momentarily just before the knob hits its maximum level.


The LFO provides seven Waveform options—ramp up, ramp down, triangle, sine, square (positive voltage, only), noise, and sample-and-hold. The ramp and sine waves are new to the Polivoks design.

Another addition is the various ways the LFO Rate can be altered, which is determined by the MIDI/FilterEG switch (located above VCO 1). When set to MIDI (switch up) the Depth knob gains control over Rate; patch a ±10V signal into the Modulation jack and Depth acts as an attenuverter that changes the amount of influence the incoming voltage has over the LFO speed.

In FilterEG mode (switch down), Depth acts as an attenuverter and the VCF Sustain knob gains subtle control over the main LFO rate: As you turn VCF Sustain up, the LFO rate increases when Depth is set to a positive level, and decreases when Depth is a negative setting. External voltages still influence the LFO rate.

The Internal Input knob acts as a level control when an external signal is patched into the rear panel. (The input jack includes a soft limiter.) If nothing is plugged into the external audio input, the knob introduces internal feedback by sending the VCA output into the mixer, which resonates nicely at extreme settings.

The knob and switch to the right control pulse-width modulation (PWM) over VCO 2, using the VCA EG (switch up) or LFO speed (switch down). The knob sets the amount of PWM. One of my favorite ways to use this feature is to control the PWM and filter cutoff simultaneously (with a touch of resonance) using the LFO’s S&H. The result is a randomized bubbling pattern of metallic tones.


The VCF and VCA have their own 4-stage envelope generators, each with 2-stage retriggering capabilities that go into audio rate (giving you additional ways to introduce rich sidebands). When using the retriggering feature, the Attack the Decay knobs control rate, while Sustain offsets the CV output’s phase, further shaping the repeating cycle. The VCA provides both self-retriggering and note-on retriggering options, as well as the ability to add modulation from the LFO.

This ability to combine the EGs in various ways is perfect for creating wild, unsynchronized polyrhythms that can be sped up into noisy broadband timbres (even before you add the LFO or crank up the internal-feedback knob). My favorite VCA trick is to set the retriggering rate differently from the LFO rate, then use the VCA’s LFO Depth knob to modulate the retriggering. The tone becomes especially rich when the LFO is running at audio rate.

Another important part of the Polivoks sound comes from the 2-pole (12 dB/octave) filter. Its pleasantly aggressive timbre is due, in part, to an unusual design that eschews capacitors and uses the capacitance of the op amps, instead. As with the original model, it offers bandpass and lowpass modes, with knobs for frequency cutoff, Resonance, LFO Depth and EG Depth. You can control frequency cutoff using the dedicated CV input, and the synth’s audio input lets you filter externally generated sounds.

Despite its reputation for being strident, the Polivoks filter can also produce the lush, mellow tones you would expect from a vintage analog design. But the VCF really growls when you take advantage of its modulation capabilities or kick it into resonance.


The Polivoks can be controlled via MIDI and with standard 1V/octave CV and gate signals. There are individual CV inputs for the LFO rate, for the pitch of each VCO, and for filter cutoff; a trigger input for the VCA; and a gate input that can be used in conjunction with the self-retriggering modes to create rhythm patterns (when the VCF switch and/or both VCA switches are in the down position).

All of this connectivity makes it easy to use the Polivoks with a Eurorack system (with the help of minijack-to-1/4" cables) as well as a DAW.

The Polivoks only responds to Note On and Pitch Bend, the latter set to a semitone in either direction, but a significant improvement since the original didn’t have a pitch-bend wheel. The MIDI channel is changed using the Reset button on the back.

Returning to the lower left panel, you’ll find Portamento and Master Volume controls (in addition to Tune and Depth), as well as the 1-voice/2-voice switch. In duophonic (2-voice) mode, the Portamento control only affects VCO 1: As you play single notes using a keyboard controller, the oscillators will move to the next note at different rates based on the Portamento amount (e.g., VCO 1 will move more slowly than VCO 2 unless Portamento is turned off ).

When playing contrapuntally, VCO 1 is automatically assigned to the upper voice. Consequently, the lower voice (VCO 2) jumps immediately to the next note, while the upper voice (VCO 1) moves at the rate set with the Portamento control. It can be a very musical effect when a touch of glide is added to one of the voices.


Like the original, the new Polivoks is unusual, somewhat quirky, yet extremely musical. The features are well-implemented and offer a broader timbral palette than you would expect, but one capable of reaching beyond that of the original model thanks to the added features.

Priced at two grand, however, the Polivoks is clearly not for everyone. But the price is certainly justifiable considering that only 100 of these units are being made, and nothing about this synthesizer sounds or feels cheap.

The bottom line is that the Polivoks is a highquality, boutique instrument in a class all its own.

Unique and musical sound. Duophonic. Rich modulation capabilities. Heavy-duty build.

Sparse MIDI implementation. Expensive. No headphone output.


Gino Robair is editor in chief of Electronic Musician and